Addressing the fireworks, I do think a BW view would afford you better, clearer views than any at BCV. I like BWV over BCV because it offers a few more amenities and the walk to Epcot and HS isnt bad. As another poster said, as a DVCer you can show your member card and gain access to Top of the World at BLT, stay inside if you prefer and get some great views of Wishes.
Our DS who is 20 now has had sensory issues since he was a kid. Auditory processing was a part of it which seems to make his hearing more sensitive. I wanted to share this with you because as they years have passed, the fireworks dont seem to bother him as much as before. Loud noises still seem to get the best of him from time to time but its almost like the fireworks come with anticipation knowing when they will blast and he compensates for it. I know as his parents, we liked the assurance from those that had been there done that, things for him would get better.